Electrode



Oct. 7, 1941.- G. ADOLPH ET AL ELECTRODE Filed Nov. 12, 1936 dusxcwAdoiph,

@ CB Z Va-((1.4 ATT RNE-YS ticularly to an anode suitable for the production Patented Oct. 7 1941 ELECTRODE Gustav Adolph, Solln, Germany, and M E. Bretschger, Buffalo, N. Y., assignors to Buffalo Electra-Chemical Company, Inc., Buffalo, N. Y.

Application November 12,1936, Serial No. 110,520" 4 Claims. (01.204-289) This invention relates to an electrode andparof percompounds by anodic oxidation. I in the production of percompounds, such as per-sulfuric acid, perboricacid, etc., and their salts, it has been found that platinum anodes must always be employed as all other metals do not permit of a deposit of the desired anion on the acid or its salt, such as $04 on sulfuric acid or a salt thereof, even though the metal might be sufliciently stable against attack by the electrolytic solution;

Because of the high price of platinum, it has always been the endeavor of the trade to construct anodes employing the mi'nimumamount'of platinum. or to replace I sible with cheaper materials. Thus, the current '1 platinum wherever posconducting rod has been made of copper or other i highly conducting materials. However, where,

common metals. copper for instance, are used as the conducting. rod, the common metal must be protected against attack or the anode solution and the nascent oxygen adjacent thereto by more or less efficient coatings or coverings impervious' to attack by these chemicals. Hard rubber has been found to be an eflicient coating =material. r In all these'cases, however,'the coating ma terial is subject to attack in the courseot time by the nascent oxygen developed at the platinum conductance wire, forming a channel therein pervious to the solution whereby the copper lead to attack. with the ultimate ,1

rod would be pronedestruction of the contact between the copper leadwire and. the platinum tip.

It is an object of the present invention to eliminate the possibility of, attack of the hard'rubber coating by nascent oxygen and protect the contact between the conducting core rod of common metal and the anode tip of platinum.

Other and further objects and advantages of. the invention appear hereafter and be more particularly pointed out in the claims.

.The drawing shows a view in perspective of the improved anode.

Referring more particularly to the drawing,

the anode of the present invention is formed of a central conducting core or rod- III of a common. metal, as, for instance, copper. Electrical contact and connection is made between rod- 10 and a conducting element H of metallic tantalum.

Surrounding. and enclosing copper core or rod III is a hard rubber sheath l2 formed with lips l3 which engage the tantalum member H. The anode is completed by connecting the platinum tip M to the tantalum member II.

It will beseen from the minimum of platinum is used and an anode wherein attack of thehard rubber sheath or covering over the copper conductor has been eliminated by the interposition of the tantalum member ll between the copper core l0 and platinum tip l4 since tantalum is a good electrical conductor but, however,'no nascent oxygen is developed upon the tantalum and, further, the tantalum .member is stable against and toward the electrolyte, which property is described German- Patent No. 386,514.

What is claimed is:

1. An anode for the production of percom- I pounds comprising a-core of conducting material, a sheathof non-conducting material stable toward the electrolyte of the bathin which the anode is used surrounding the corepa platinum tip'upon which nascent oxygen develops when the anode is used in the production of percompounds spaced from the sheath, and a memberof tantalum extending through the sheath and being co the platinum tip so that when in use no nascent oxygen-develops in contact with the sheath.

An anode for the production of percom pounds comprising a core of copper, a sheath of non-conducting material surrounding "the cop- ,per core, a platinum tip spaced from the sheath and a member of tantalum extending through the sheath and having electrical contact with the core and the platinum tip so that when the anode I is used for the production of percompounds nascent oxygen'develops only upon the platinum tip and not in contact withthe sheath.

'3.""In an electrode, an elongate elementof conducting material, a second elongate elementoi electrochemically active conductingmlaterial ex-' tending parallel thereto and spaced therefrom, an insulating sheath surrounding said first element, and a plurality of electrochemically inactive conductors extending through said insulati ng sheath and between said two elements for maintaining rigid relation and for establishing electrical communication tlrierebetween.-

4. In an electrode, an elongate element of a .metallic conducting material, a second elongate element comprising electrochemically active conducting tnaterial of platinum extending parallel to said first element and spaced therefrom, an insulating sheath surrounding said first element,

- and a plurality f electrochemically inactive conforegoing that the present invention provides an anode wherein a' ductors formed of tantalum and extending between laicl two elements for maintaining rigid relation and for establishing electrical communication therebetween.

GUSTAV ADOLP/H. MAX E. BRE'I'SCHGER.

nnected electrically to the core and to 

